Process for making gas



J. U. McDONALD.

PROCESS FOR MAKING, GAS. APPUCATION HLED MAR, 10, 1920.

'1,367,321. Patented Feb. 1, 1921.

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JOHN URBAN MODONALD, OF DECATUR, ILLINOIS.

PROCESS FOR MAKING GAS.

Specification of Letters Patent.

Patented Feb. 1, 1921;

Application filed March 10, 1920. Serial No. 364,651.

T 0 all whom it may concern:

Be it known that I, J OHN URBAN McDon- ALD, a citizen of the United States, and residin at Decatur, in the county of Macon and tate'of Illinois, haveinvented a new and Improved Process for Making Gas, of which the followin is a specification.

My invention re ates to the manufacture of gas for heating, illuminating and power purposes by the destructive distillation of carbonaceous matter, especially coal, peat, saw-mill refuse, wood, garbage and other or anic material in general.

he object of this invention is the production of permanent ases from wet carbonaceous material at minimum cost without the use of the expensive mineral oils now usually employed.

further object of this invention is the conversion of all of the gas producing constituents of the carbonaceous material including the tar, and the moisture content, into gas, so as to thereby obtain a maximum revenue from the material acted upon.

This invention consists in heating the wet gas producing material in a retort which is so constructed that the steam and gases produced by such heating cannot escape from above the heated zone but are forced down by their own pressure through the heated zone where chemical action causes the gas producing material to become intensely hot and thereby also causes an increased production of gases which are carried away from below the incandescent material.

The invention further consists in conveying the gas from below the highly heated gas-forming material through fresh amounts of such material so that the heat of the gas will be conserved by communicating it to the fresh gas-forming material.

The accompanying drawing represents a diagrammatic section of a device which may be employed to carry this process into effect. The retort 1 ma be of any desired cross section but is pre erabl cylindrical and is mounted in a heating c amber 2 so that it ma be highl heated, particularly interme iate its en The heating chamber connects to a furnace 3 and may be provided with a flue 4 and an auxiliary air passage 5. Any other desired type of heating device may be employed.

bove the retort is mounted a feeding chamber 6 provided with spiders 7 to support the helical conveyor 8 by means of i which the wet gas producing material 9 is fed down into the retort, should such material fail to be moved by gravity, the rate of such feeding depending upon the charactor of the material, the heat that is maintained in the retort, and the rate of reduction of the material to gas. The conveyor is shown mounted on a shaft 11 having a bevel gear 12 near one end, which gear meshes with the bevel gear 13 on the shaft 14 that is driven by a motor 15 by means of a belt 16.

Above the feeding chamber is a charge chamber 17, and between the two chambers is a valve 18. Above the charge chamber is shown a hopper 19 of any desired construction, while a valve 20 is placed between it and the charge chamber. The carbonaceous material is permitted to fall into the charge chamber 17 in batches, after which the valve 20 is closed and the valve 18 0 ened to permit the batch to fill the fee ing chamber from which the material passes to the retort at a constant rate. fter the desired amount has fallen into the feeding chamber the valve 18 is closed to prevent the escape of ases from the feeding chamber.

The retort is heated to such a temperature that a portion of the carbonaceous material becomes incandescent and the volatile portions thereof are driven off. At the same time, the moisture in this material becomes super-heated steam, a pressure of mixed gas and steam accumulatin in the upper part of the retort and resultingin as and steam being forced down through t e hot carbonaceous material.

The steam in passin through the bed of incandescent carbon becomes dissociated, the oxygen combines with the carbon to produce carbon monoxid and dioxid, the hydrogen upon being liberated mixes with the mass of combined ases, a fractional portion unitin with car ii to form marsh gas (CH ll of the gas producing material is therefore changed to gas. The gases thus produced collect below the incandescent zone and pass out through the pipe 22. If the amount of moisture in the carbonaceous matter is below the maximum that can be properly split up in the retort, a pro er amount of superheated steam may be a ded through the pipe 24 which connects to any proper source of supply.

The waste passes to the bottom of the retort intoa trough 26, from which it is removed in any desired manner. In the drawing, a screw conveyer 27 is shown which carries the waste to a passage 28 controlled by a valve 29. This passage opens into a chamber 30 containing a screw conveyer 31 which discharges the waste into a receptacle 32. The two conveyers may be driven by a motor 33.

The gas from the pipe 22 may be passed through the charge in t e chamber 17 where it gives off its heat to the fresh material therein, and then passes to the pipe 34 through the pipe 37. The three-wa valve 36 connects into the pipe 22 and to the pipe so that the gas may pass directly to the ipe 34 without passing through the chamer 17. A check valve 38 prevents a return flow of the gas into the chamber 17 The temperature of the heater ma be controlled in any desired manner. he contents of the retort may be stirred up through the valve controlled openings 39 and 40. The principal departure of this process from the prior art lies in the production of gases and very hot steam above a zone or bed of incandescent carbon in a chamber of such construction that the gases and steam are forced by their own pressure through this intensely hot zone, resulting in the production of a maximum amount of heating and power gases.

claim The process of making gas consisting in introducing wet garbage into the top of a vertical retort, heatin an intermediate zone of the retort suflicient y to render the fixed carbon of the arbage incandescent at that point, thereby eating the garbage above the incandescent zone sufliciently to vaporize the moisture and gasify the volatile matter of the garbage, the resultant gases, tar vapor and steam being forced down by their own pressure through the incandescent layer causing all the incandescent carbon to oxidize to form fixed gases which pass down with the gases of the volatile matter through the ashes in the bottom of the retort, thereby causing the total gasification of the combustible constituents of the garbage.

JOHN URBAN MCDONALD. 

